During interventional pain management, drugs are injected into the patient's body to reduce and otherwise manage pain and, in certain cases, to assist in the identification of the source of pain. The most commonly performed procedure to relieve pain is an epidural steroid injection where a powerful cortisone solution is injected directly to the spine to reduce swelling and irritation around a nerve or part of the spinal cord. In a second procedure, referred to as selective nerve root injection, fluoroscopy provides X-ray guidance to enable a drug to be injected directly into a troubled nerve root rather than into the entire spine. In facet joint injection, medication is injected directly into a facet joint, again relying on the aid of fluoroscopic X-ray guidance. In yet another procedure, an injection is made into the sacroiliac joint. Interventional pain management also includes injections of corticosteroids directly into an affected joint or soft tissue space.
Knowing the precise depth and position of the needle is critically important to the effective introduction of the pain management drug and, just as importantly, to avoiding serious complications. Therefore, as noted above, each procedure is simultaneously guided by anterior-posterior, oblique, and lateral fluoroscopy.
Even with fluoroscopic guidance, however, interventional pain procedures at the cervical and thoracic spine present a number of challenges to the pain practitioner. This is often due to the inability to obtain an optimal fluoroscopy view of the lower cervical and thoracic spine. Compromised fluoroscopic viewing can derive from a number of sources, including fluoroscopic obstructions presented by the patient support arrangement and challenges in patient positioning. Both are largely beyond the control of the practitioner under the present state of the art.
Under current medical practices, common patient positioning options include the prone, supine, and recumbent positions, the left and right lateral decubitus positions on a horizontal table, and the sitting position in a chair or on a table. The recumbent and lateral decubitus positions offer patients comfort but can create difficulties with fluoroscopic visualization of the spine. For example, when a patient is in the prone position, the lower cervical segments are sometimes difficult to visualize in the lateral view due to the patient's shoulder obstructing the X-ray beam.
Pain practitioners use several techniques seeking to improve the visualization of the lateral view of the lower cervical region. They sometimes ask the patient to simulate a swimming position with one shoulder up and the other down or to pull both shoulders down. In other cases, practitioners place a pillow under the patient's shoulders to improve the cervical curvature. Practitioners also sometimes increase the X-ray beam for better X-ray penetration. Although these measures work for some patients, they do not work for everyone and often do not fully resolve the issue. For example, some patients cannot obtain these positions. In other cases, the positions do not improve visualization. Furthermore, such measures are time consuming and increase the radiational exposure for the patient and the staff.
It is also difficult to visualize the interlaminar spaces in the thoracic spine because of the significant caudal angulation of the spinal processes. To obtain a better view, interventionalists often put a pillow under the chest to increase thoracic curvature and thus to open the intralaminar spaces. Alternatively, the procedure can be done in the sitting or lateral decubitus position to provide better flexion of the thoracic spine.
The seated position is known to be advantageous in that it offers better visualization of the lower cervical and the thoracic spine and enables improved access for fluoroscopy guided procedures. Gravity pushing the patient's shoulders down facilitates visualization of the lower cervical segments. Additionally, it is easier to extend or bend the neck in the sitting position compared to the lying position. The seated position also gives more freedom to permit flexibility of the thoracic spine thus easing the fluoroscopy of the thoracic intralaminar spaces and facilitating access to the thoracic epidural spaces.
For the lumbar spine, the sitting position can be preferred for many reasons, one being a patient's inability to tolerate the recumbent position, such as due to severe low back pain. For patients with severe breathing conditions, such as COPD, CHF, and asthma, and wheelchair dependent or morbidly obese patients, the sitting position may be the only solution for performing spinal procedures at any level: lumbar, thoracic, or cervical.
In the absence of dedicated equipment, doctors commonly use a number of techniques to modify the existing medical and non-medical apparatuses for this procedure. For example, the patient can be seated in a massage chair, a regular patient chair with a step stool under the feet, a regular chair with the chin on the fluorotable, and other ad hoc positioning arrangements. While they can at times be simple to administer, these methods create health and safety problems for the patient and the pain practitioner. For example, such positioning arrangements lack a radiolucent chest and chin support whereby fluoroscopic viewing can be obstructed. Furthermore, the practitioner is often unable to obtain optimal fluoroscopic views in each of the anterior-posterior, oblique, and lateral planes.
Positioning methods of the prior art also often require lengthy and complicated emergency supine patient repositioning. However, in an emergency situation, such as a vasovagal reaction, anaphylactic shock, or disrythmias, every second before emergency assistance can be provided is critical. As the present inventor has appreciated, quick and safe supine repositioning can be life saving.
With a knowledge of the state of the art as summarized above, the present inventors have appreciated that there is a need for a chair for fluoroscopy that provides safer and more comfortable positioning for the patient and more effective and convenient fluoroscopy of the upper, middle, and lower spine. There is also a need for an apparatus that allows the patient to remain in a forward-leaning and relaxed seated position when fluoroscopy of the cervical, thoracic, or lumbar spine is taken during interventional procedures. Still further, there is a need for a fluoroscopy chair that allows quick supine repositioning of the patient. A fluoroscopy chair meeting these and further needs that the prior art has failed to meet adequately would represent a significant advance in the field and a substantial benefit to patients and doctors.